Preparation of alkylidene bisphenols



United States Patent 3,367,980 PREPARATJIQN 0F ALKYLIDENE MSPHENGLSEdward F. Zawesiri, Royal Gait, Mich, assignor to Ethyl Corporation, NewYork, N.Y., a corporation of Virginia No Drawing. Filed July 15, 1955,Ser. No. 472,345 11 Claims. (Cl. 266-619) This invention relates to animproved process for the preparation of alkylidene bisphenols.

It is known that alkylidene bisphenols can he prepared by the react-ionof a phenol with a carbonyl compound in the presence of an acid or basecatalyst. This reaction may also be carried out in a solvent asdescribed in US. Patent 2,807,653. The rate of reaction when usingcertain phenols, especially alkylated phenols, however, is frequentlyquite slow, taking days to obtain any appreciable yield of thealkylidene bisphenol product. There is a need then 'for improving orincreasing the reaction rate for this type preparation.

An object of this invention is to provide an improved process for themanufacture of alkylidene bisphenols. A further object of this inventionis "to provide a process for producing alkylidene bisphenols wherein thereaction rate is increased substantially. Other objects of thisinvention will be made clear in the detailed description and claims tofollow.

These and other objects of this invention are accomplished by thereaction of a phenol having the formula (I)II with a carbonyl compoundhaving the formula 0 R3(|.LR4

wherein R R R and R are independently selected from the group consistingof hydrogen, alkyl radicals containing 1-1 2 carbon atoms, aryl radicalscontaining 6-12 carbon atoms, aralkyl radicals containing 7-12 carbonatoms and alkaryl radicals containing 7-12 carbon atoms, in the presenceof a sul'foxide having the formula 0 ll Rs-S s III.

The pictorial designation of R and R in Formula I indicates that R and Rmay be located on the benzene ring in the positions ortho and para tothe hydroxyl group. Thus, R and R may both be ortho to the hydroxy groupor one may be ortho and the other may be para to the hydroxy group.

A preferred embodiment of this invention is a process comprising thereaction of the phenol (Formula I) wherein R and R are selected from thegroup consisting of hydrogen, alkyl radicals containing 1-12 carbonatoms and alkaryl radicals containing 7-12 carbon atoms with a carbonylcompound (Formula :11) wherein R and R are selected from the groupconsisting of alkyl radicals containing 1-12 carbon atoms, in thepresence of a sulfoxide (Formula 111) wherein R and R are alkyl radicalscontaining 1-8 carbon atoms.

A more preferred embodiment of this invention is a process comprisingthe reaction of a phenol (Formula I) wherein R and R are selected fromthe group consisting of hydrogen and alkyl radicals containing 1-12carbon "ice atoms with a carbonyl compound (Formula II) wherein R and Rare alkyl radicals containing 1-12 carbon atoms in the presence of asultoxide (Formula 111) where in R and R are alkyl radicals containing1-8 carbon atoms.

A highly preferred embodiment of this invention is a process comprisingthe reaction of a phenol having the formula:

(IDI'I wherein R is an tat-branched alkyl radical containing 3-12 carbonatoms and R is an alkyl radical containing 1-12 carbon atoms, with acarbonyl compound (Formula 11), wherein R and R are alkyl radicalscontaining 1-12 carbon atoms, in the presence of a suifoxide (FormulaIII), wherein R and R are alkyl radicals containing l-8 carbon atoms.

The phenols useful in this process are organic compounds in which atleast one hydroxyl group is attached directly to a carbon atom in abenzene ring and in which at least one reactive position, i.e., an orthoor para position, on the benzene ring is open, that is, bonded tohydrogen. Phenols which will react with a carbonyl compound to form abisphenol product may be used in this process. This includes substitutedphenols, that is, phenols in which one or more of the hydrogen atoms onthe benzene nucleus have been replaced by another atom or group.Examples of phenols useful in the process include: o-et'hylphenol;p-n-butylphenol; p-n-dodecylphenol; o-(Z- ethyl-n-heptyDphenol;p-isopropylphenol; o-n-hexylphenol; 2-methyl-6-n-dodecylphen0l;2-n-undecyl-6-n-pentylphenol; 2-n-hexyl-6aisopropylphenol;2-n-butyl-4-n-dode cylphenol; 2-n-octyl-4-(l-methyl-n-heptyl) phenol;2,6-diethylphenol; 2,4 diundecylphenol;2,6-di-(.l-methyl-npentyl)phenol; Z-phenylphenol;4-(4-biphenylyl)-phenol; 2-tt-naphthylphenol; 2,4-dibenzylphenol;2-(4-ethylphenyl) 6 (3 phenyl-n propyl) phenol;2--n-propyl-4-(3-biphenylyl) phenol; 2-(4-phenyl-n-hexyl)-4-butylphenol;2- methyll-chlorophenol; o-bromophenol; 2-n-heptyl-6-chloropnenol;2-isobutyl 4 chlorophenol; 2-cyclohexyl-4-npentylphenol, and the like.

Monoand di-substituted phenols in which alkyl groups containing fromabout 1-12 carbon atoms, or alkaryl groups containing from about 7 toabout 12 carbon atoms, are the substituting groups, are preferred. Themono-substituted phenols are those in which only one phenolic benzenering hydrogen is replaced by another group (or atom). Examples of thesepreferred mono-substituted phenols include: o-n-propylphenol;p-n-octylphenol; o-(lmethyl-n-butyDphenol; p-n-decylphenol;o-n-heptylphenol; o-(2,2,'3,3-tetramethyl) phenol; p-heptylphenol; p-6-phenyl-n-hexylphenol; o-benzylphenol; p-(2-phenyl-n-pro p-yl)'phenol;p-cresol; p-'(a-methylbenzynphenol; o-(a,adimethylbenzyl) phenol and thelike. Di-substituted phenols are those in which two benzene ringhydrogen atoms are replaced by other atoms or groups. Examples of somepreferred di-subst-ituted phenols are: 2,4-di-methylphenol;2,6-di-n-heptylphenol; 2 methyl-4-(4-phenyl-n-butyl)phenol;2-phenethyl-6-(2 methyl-n-propyl)phenol; 2,4-di-(6-phenyl-n-hexyDphenol; 2,6 dibenzylpheuol; 2-n-dodecyl- 4-bromophenol;2-(2,2-dimethylethyl) 6 chlorophenol; 2,6-(2 methylbenzyl)phenol;2-(2-methylbenzyl)-4-n-butylphenol and 2n-pentyl-6-(u,ot-dimethylbenzyl)phenol.

Substituted phenols which have at least one alkyl group in the orthoposition are more preferred in carrying out this process. These arecommonly called orthoalkylated phenols. Preferably, the alkyl group hasfrom 1 to about 12 carbon atoms. The mono-orthoalkylated phenols haveonly one alkyl group in the ortho position. Some examples of the morepreferred mono-orthoalkylated phenols include: o-cresol;o-isopropylphenol; o-isobutylphenol; o-ndecylphenol; o-n-hexylphenol;o-n-undecylphenol; o-nnonylphenol; o-sec-butylphenol and the like.

Di-orthoalkylated phenols which are more preferred have alkyl groups inboth positions ortho to the hydroxyl group. Examples of the morepreferred phenols include: 2 ethyl 6 n dodecylphenol; 2 n pentyl 6nnonylphenol; 2 methyl 6 (2 ethyl n hexyl) phenol;

2,6 di n propylphenol;.2,6 di (3 7 methyl 11 undecyl)phenol; 2,6 di noctylphenol; 2 n octyl 6- n-decylphenol and the like.

The 2,6-di-substituted phenols (Formula IV), wherein at least one of thesubstituting groups is an a-branched alkyl radical, are highly preferredin this process. By tit-branched alkyl radical is meant an alkyl radicalWhich is attached directly to the benzene ring through a secondary ortertiary carbon atom. When phenols are substituted in the 2,6-position,they are often described as hindered phenols. The groups in thepositions on the benzene ring adjacent to the hydroxyl group stericallyhinder the hydroxyl group, there-by preventing easy access to this groupby other chemical agents. The wbranched alkyl radicals are especiallyeffective in their hindering action. Examples of these highly preferredphenols include: 2 isopropyl 6 methylphenol; 2 (1 methy1- n octyl) 6hexylphenol; 2 (1 methyl n undecyl)- 6 n dodecylphenol', 2 isobutyl 6 npropylphenol; 2,6-di-sec-butylphenol and 2,6-diisopropylphenol.

A most preferred phenol is 2,6-di-tert-butylphenol.

The carbonyl compounds are organic compounds which contain thefunctional group in the configuration as illustrated in Figure II. Anycarbonyl compound which will react with a phenol to form an alkylidenebisphenol may be used in this process. These compounds include bothaldehydes and ketones. The aldehydes have two hydrogen atoms or onehydrogen atom and one hydrocarbyl radical attached directly to thefunctional group. Preferably, this hydrocarbyl radical should containfrom 1 to 12 carbon atoms. It can be an aryl radical, a substituted arylradical, an alkyl radical or a substituted alkyl radical. Examples ofuseful aldehydes are: formaldehyde, hexanal, dodecanal, benzaldehyde,4-phenylbenzaldehyde, S-phenylpropionaldehyde, 2- methylbenzaldehyde,fi-naphthylaldehyde, and the like.

Ketones have two hydrocarbyl radicals attached directly to thefunctional group. In some cases, the hydrocarbyl radicals may beconnected at their terminal ends to form cyclic ketones such ascyclohexanone. These hydrocarbyl radicals preferably contain from 1 toabout 12 carbon atoms. These radicals may be aryl radicals, substitutedaryl radicals, alkyl radicals and substituted alkyl radicals. Sincethere are two such radicals in the ketone structure, they may both bethe same as for example in diethyl ketone or they may be different asfor example in n-butyl phenyl ketone. Examples of useful ketones are:levulinic acid, methyl-n-dodecyl ketone, n-hexyl-n-decyl ketone,di-n-pentyl ketone, phenethyl-(4-biphenylyl) ketone,benzyl-(6-phenyl-n-hexyl) ketone, di(2-n1ethyl-n-hcxyl) ketone,n-dodecyl-(3-biphenylyl) ketone, dibenzyl ketone,ethyl-(3-phenyl-n-propyl) ketone, a-naphthyl methyl ketone, diphenylketone, benzophenone, isobutyl-n-hexyl ketone and the like.

The alkanals and the dialkyl ketones are preferred carbonyl compoundsuseful in this process. Alkanals are alkyl aldehydes. It is preferredthat the alkyl radicals contain from 1 to about 12 carbon atoms.Examples of preferred aldehydes and ketones include: acetaldehyde,heptanal, decanal, methyl-n-hexyl ketone, diisopropyl ketone,di-(Z-methyl-n-hexyl) ketone, n-hexyl-ndodecyl ketone, and di-n-decylketone.

The more preferred carbonyl compounds which are useful in this processare the low molecular weight d-ialkyl ketones. The alkyl groups may beprimary, secondary, or

tertiary and contain from 1 to 4 carbon atomsI'Ex'arnples of theseketones include: methyl ethyl ketone, diethyl ketone, methyl isobutylketone, diisobutyl ketone, ethylsec-butyl ketone, isopropyl n-butylketone, and di-npropyl ketone.

A most preferred carbonyl compound is acetone.

The sulfoxides are illustrated by Formula III. Typically, they can beprepared by the oxidation of the corresponding sulfides. Commercially,some sulfoxides are recovered as by-products in the manufacture ofpaper. When a phenol/ carbonyl compound condensation reaction is carriedout in the presence of a sulfoxide, the rate of reaction and/ or yieldof the alkylidene bisphenol product are significantly increased. Thesulfoxide therein acts as a promoter. Examples offered later willfurther illustrate this activity. Since the sulfoxide acts as apromoter, any

sulfoxide or mixture of sulfoxides may be used in the i process. Thesubstituents R and R in Formula III may be any hydrocarbyl radicals withfrom 1 to about 12 carbon atoms. This includes both aryl and alkylradicals. Examples of useful sulfoxides are methyl n-butyl sulfoxide;n-methyl n-octyl sulfoxide; di-n-pentyl sulfoxide; di-n-octyl sulfoxide;methyl phenyl sulfoxide; n-butyl ocnaphthyl sulfoxide; isobutylfl-naphthyl sulfoxide; n-octyl (4-biphenylyl) sulfoxide; diphenylsulfoxide; phenyl anaphthyl sulfoxide; phenyl (3-biphenylyl) sulfoxide;ccnaphthyl (4-biphenylyl) sulfoxide; diisopropyl sulfoxide and n-heptyl(Z-ethyl-n-hexyl) sulfoxide.

In general, dialkyl sulfoxides are more preferred in this process. Thedialkyl sulfoxides may be symmetrical or unsymmetrical. Symmetricaldialkyl sulfoxides will have identical alkyl groups bound to the sulfuratom. Examples of these symmetrical sulfoxides are: diethyl sulfoxide,di-n-butyl sulfoxide, diisopropyl sulfoxide, din-heptyl sulfoxide,di-(3-ethyl-n-pentyl) sulfoxide, and the like. Where different alkylgroups are bound to the sulfur atom, the dialkyl sulfoxides are termedunsymmetrical. Examples of these include: n-butyl-n-octyl sulfoxide,methyl isobutyl sulfoxide, n-pentyl n-hexyl sulfoxide,ethyl(Z-methyl-n-heptyl) sulfoxide and the like.

A most preferred sulfoxide is dimethyl sulfoxide.

In carrying out the process of this invention, the ratio of phenol tocarbonyl compound may be varied over a wide range. For example, the moleratio of phenol to carbonyl compound may be varied from 10:1 to 1:10. Apreferred mole ratio of the phenol to carbonyl compound is from 2:1 to1:10. A most preferred mole ratio range of phenol to carbonyl compoundis 2:1 to 1:2.

The sulfoxide as used in the invention acts as a promoter, as previouslydescribed. It is a requirement of the process of this invention that asulfoxide or any mixture of sulfoxides be present with the phenol andcarbonyl compound. Since the sulfoxide acts as a promoter, the quantityof sulfoxide present in the reaction mixture may be varied over a widerange. The sulfoxide may be present in quantities such that it might actas a solvent or reaction medium. The sulfoxide may be used together withother media in solvent quantities. These other media should be inertunder the conditions of the condensation reaction. They should notprevent the sulfoxide from functioning as a promoter. Examples of suchmedia include the alcohols such as isopropanol, ethanol and amylalcohol; ethers such as dibutyl ether, dimethyl carbitol, dioxane andtetrahydrofuran; and hydrocarbons such as hexane, xylene and toluene.

It is to be understood that the condensation reaction can also becarried out without the use of a diverse reaction medium. In other wordsthe process of this invention can be carried out in a reaction mediumconsisting essentially of a sulfoxide.

Regardless of the reaction system used, the sulfoxide must be present inat least promoter quantities. A promoter quantity is that amount ofsulfoxide which will effect improvement in the rate and/ or yield of thephenol/ carbonyl compound condensation reaction. As little as 40 partsby weight of sulfoxide, per 100 parts by weight of reactant phenol iseffective as a promoter. There is no critical upper limit in the amountof sulfoxide. The upper limit of sulfoxide which is used is determinedfor example by the dilution level which may be desired, reaction vesselsize, or other similar factors. Amounts of sulfoxide as high as 2,000parts by weight for every 100 parts by weight of reactant phenol may beused. Greater and lesser amounts of sulfoxide may be used provided thata promoter quantity is employed.

The presence of a small amount of an acidic or basic substance is knownto catalyze the condensation of a phenol and a carbonyl compound. Theuse of a catalyst is generally preferred even where the sulfoxide ispresent and acts as a promoter. Since the catalyst remains unchangedafter the reaction is complete and may be retained in the product as animpurity, it is desirable that the catalyst be soluble in water. Commonacid catalysts used are the strong mineral acids such as sulphuric acid,phosphoric acid, hydrochloric acid, organic acids such as p-toluenesulfonic acid and acid salts such as calcium chloride. A preferred acidcatalyst is hydrochloric acid. Basic cata.ysts commonly used are thehydroxides of the alkali and alkaline earth metals such as sodiumhydroxide, potassium hydroxide and calcium hydroxide. Potassiumhydroxide is a preferred basic catalyst.

The effectiveness of a catalyst is normally such that a very smallamount is satisfactory to initiate the reaction. The quantity of acid orbase catalyst which is used in the invented process can, nevertheless,be varied over quite a wide range and still be effective. The amount ofcatalyst used can range from 0.01 percent to about 30 percent based onthe weight of the reactant phenol. The preferred amount of catalyst usedis 0.01 percent to about 7 percent based on the weight of the reactantphenol.

According to the process of this invention, condensation of a phenolwith a carbonyl compound can be accomplished over a very wide range oftemperatures. The nature of the reaction system, that is, the physicalstate of the reactants at various temperatures, the type of reactionmedia employed, and other such factors, will have an influence ondetermining the most desirable tempera ture to use. The presence of thesulfoxide promoter will allow the process to be carried out efficiently,at a temperature lower than would be required if the sulfoxide were notpresent. Thus, the process of this invention can be conducted attemperatures ranging from 50 C. to 250 C. The preferred temperaturerange is 50 C. to about 180 C.

Depending on the temperatures used and the nature of the reactionsystem, the process may be conducted under widely varying pressureconditions. The pressure is not critical. Thus, if a highly volatilereaction ingredient is present and comparatively high temperatures areemployed, pressures above atmospheric may be used to keep the volatileingredient in a non-vaporous state. The process can be carried out underreduced pressure, if required. The reaction will proceed with equalfacility at normal atmospheric pressure.

The nature of the reaction system, the temperature used, and otherfactors such as percent yield desired, contamination level of theproduct, and degree of unwanted side reactions, will be taken intoconsideration when setting the reaction time. Use of the sulfoxide topromote the reaction shortens the reaction time which would be requiredto produce a like amount of alkylidene bis-phenol, were sulfoxide notpresent. Thus, if a particular condensation reaction requires eighthours to yield 10 percent of an alkylidene bisphenol where sulfoxide isnot present, with the sulfoxide added, the same reaction under the sameconditions would proceed to a 10 percent yield in considerably less thaneight hours. On the other hand, if the practitioner chose, he mightallow the reaction to proceed in the presence of the sulfoxide promoterfor more than one hour in order to obtain a yield of alkylidenebisphenol heretofore unobtainable. So, the reaction may be allowed toproceed for as long a time as is required by the practitioner of theprocess. Normally, a reaction period of from 1 to about 48 hours will besufiicient. More commonly, reaction periods of from 4 to about 24 hoursare satisfactory.

The reaction may be carried out in air although an inert atmosphere suchas nitrogen is preferred.

In order to more fully illustrate the improvement in reaction rateeffected by this invention, the two following examples were carried out,The reactants were the same except that Example 1 was conducted using acon- Ventional procedure without sulfoxide while Example 2 was conductedusing dimethyl sulfoxide as a promoter. All parts and percentages in allthe examples to follow are by weight unless otherwise indicated.

EXAMPLE 1 To a reaction vessel provided with a stirrer, thermometer anda condenser was added 103 parts of 2,6-di-tertbutyl phenol, 40 parts ofacetone, 5 parts of 45 percent aqueous potassium hydroxide and 200 partsof methanol under a nitrogen flush. The stirred reaction mass was heatedto reflux and kept there for six days. At the end of this time, thereaction mass was cooled to room temperature. Five parts of concentratedHCl were added and the reaction mass was then cooled to 5 C. The solidwhich separated was then filtered off. Infrared analysis showed it to be4,4'-isopropylidene bis(2,6-di-tert-butyl) phenol. The yield was 32percent.

EXAMPLE 2 To a reaction vessel as equipped in Example 1 was added 103parts of 2,6-di-tert-butyl phenol, 40 parts of acetone, 5 parts of 45percent aqueous potassium hydroxide and 250 parts of dimethyl sulfoxideunder a nitrogen flush. The stirred reaction mass was heated to 110 C.and held there for 24 hours. The reaction mass was then cooled to 12 C.and neutralized with concentrated hydrochloric acid. Water was thenadded to the reaction mixture and the mass allowed to remain at 12 C.with stirring. After five minutes a solid separated. This solid wasfiltered off, washed with water and then recrystallized from hexane. Theproduct was identified by infrared analysis as 4,4-isopropylidenebis(2,6-di-tertbutylphenol). The yield was 50.5 percent.

Where the reaction was carried out without any sulfoxide present(Example 1), six days were required in order to obtain a 32 percentyield of the alkylidene bisphenol product. Where the sulfoxide waspresent (Ex ample 2), the yield of the alkylidene bisphenol product wvasincreased to 50.5 percent and the reaction time was reduced to one day.These results illustrate the significant improvement in the yield andreduction in the reaction time accomplished in using the process of thisinvention.

The following examples further illustrate the manner in which thisinvention is carried out.

EXAMPLE 3 A reaction vessel equipped with a thermometer, a stirrer, anda reflux condenser is charged with parts of 2-methyl-6-isopropylphenol,72 parts of methyl ethyl ketone, 5 parts of 45 percent aqueous potassiumhydroxused in Example 3.

P henol Bis-Phenol Product2-n-hexyl-6-(1,1,2,2-tetra-methyl-npropyl)phenol.

2-n-dodeeyl-6-(1,1,3,3-tetra-methyln-oetyl)phenol.

2-isobutyl-6-n-octylphenol 2-bromo-6-isopr opylphenol2-n-hexyl-4-(1,1,2,2-tetra-methyl-n propyl)phenol.

2-(l,1,3,3-tetramethyl-n-oety1)-4-n dodeeylphenol.

2-isobutyl-4-n-0ctylphenol 2-1nethyl-4-isopropylphenol 2-tert-butylphenol 4,4(1-methylpropylidene)-bis-[2- n-hexyl6-(l,1,2,2-tetraniethyl-npropylphenol].44-(methylpropylidene)bis-[2-ndodeeyl-G-(l .1,3,3-tetrarnethyl-noetyDphenol]. 4,4-(lmethylpropylidene)-bis-(2-isobutyl-G-n-octylphenol). 4,4-(l-methylpropylidene)-bis-(2-broliio-tl-isopropylphenol) 6,6-(1-methylpropylidene)-bis-2n-l1exyl-4-(1,1,2,2-tetramethyl-npropyDphenol].6,6-(l-methylpropylidene)-bis-[2- (1,1,3,3-tetramethyl-n-oetyl)-4-n-dodecylphenol]. 6, 6- (1methylpropylidene) -bis- (2-isobutylA-n-octylphenol) 6,6-(l-methylpropylidene)-bis-(2-methyl-4-isopr op ylphenol) 4,4-(l-methylpropylidene)-bis-(2-tert-butylphenol) 4,6(1-methylpropylidene)-bis-(2- tert-b utylphenol)6,6-(l-methylpropylidene)-bis-(2- tor t-butylphenol)4,4-(Lmethylpropylidene)-bis-[2- n-butyl-G-(4- ethylphenyl) phenol]EXAMPLE 4 To a reaction vessel equipped as in Example 3, are

added 452 parts of 2-isopropyl-6-benzylphenol, 120 parts ofacetophenone, 5 parts of 36 percent hydrochloric acid, and 800 parts ofdimethylsulfoxide. The mixture is heated to 120 C. with stirring. It iskept there for 4 hours. At the end of this time, the reaction mixture iscooled to room temperature. Water is added and the mixture is cooleddown to about 5 C, A superior yield of the product4,4-(u-methylbenzylidene)-bis-(2-isopropyl-6-benzylphenol) is therefromrecovered.

Following is a list of bisphenol products which are obtained when thephenols listed on the left are used in place of the2-isopropyl-6-benzylphenol in Example 4. The amount of phenol used isthe molar equivalent of the amount of 2-is0propyl-6benzylphenol used.

Phenol Bis-Phenol Product 2-(a,a-dimethylbenzyl)-6-(1,1,2,2-

tetramethyl-n-propyl)phenol.

2-isobutyl-6-(a-methylbenzyl) phenol.

2-is0propyl-4-benzylphenol 2-isopropylphenol 2-(m-dimethylbenzyl)-4-(1,1,2,2-

tetramethy1-n-propyl)phenol.

2-(6-phenyl-n-hexyl)-4-(l-methyln-undeeyDphenol.

4,4-(a-methylbenzylidene)-bis-[2- (a,a-dimethylbenzyD-(i-(1,1,22-tetramethyl-n-propyl)phenol]. 4,4-(a-methylbenzylidene)-bis-[2-(B-phenyl-n-hexyl)-6-(1-methyln-undecyl)pheno1].4,4-(a-methylbenzylidene)-bis-[2- isobutyl-G-(A-methylbenzyl) phenol].6,6-(a-methylbenzylidene)-bis(2 isoprpyl-4-benzylphenol)4,4-(a-methylbenzylidene)-bis-(2- isopropylphenol).4,6-(a-methylbenzylidene)-bis- (2- isopropylphenol).6,6-(a-methylbenzylidene)-bis-(2- isopropylphenol)6,6-(a-methylbenzylidene)-bis-[2- (a,a-dimethylbenzyl)-4-(1,1,2,2-tetramethyl-npropyl)phenol]. 6,6-(a methy1benzylidene)-bis-[2-(fi-phenyl-n-hexyl)-4-(1-methyln-undecyDphenol].

EXAMPLE A reaction vessel equipped as inExample 3 is charged with 552parts of 2-methyl-6-phenylphenol, 148 parts of methyl cyclohexyl ketone,1200 parts of dimethylsulfoxide and 3 parts of 50 percent sulfuric acid.The mixture is heated with stirring, to 70 C. and kept there for 40hours. The mixture is then cooled to room temperature. After water isadded, the mixture is stirred and cooled down to about 15 C. A goodyield of 4,4-(1-cyclohexylethylidene)-bis-(2-methyl-6-phenylphenol) isisolatedtherefrom.

Listed below are phenols and the bisphenol products which are obtainedwhen these phenols are used in place of 2-methyl-6-phenylphenol inExample 5. In each case, the amount of phenol used is the molarequivalent of the 2-methyl-6-phenylphenol used.

Phenol Bis-Phenol-Produet 4,4-(l-eyclohexylethylidene)-bis-[2-n-dodeeyl-6-(4-biphony1yl) 2-n-dodecyl-6-(4biphenylyl) phenol.

2-n-dodecyl-6-(finaphthyl) phenol 2-(3-biphenylyl)-6-n-hexylphenolZ-ethylphenol 2 methyl-4 phenylphenol Z-n-deeyl-tQ-naphthyl)phenoL2,4-diphenylphenol 2-npropyl-4(2-n-pentylphenyl) phenol.

EXAMPLE 6 To a reaction vessel as equipped in Example 3, are added 172parts of 2-(6-phenyl-n-hexyl)-6-benzylphenol, 500 parts of methyltert-butyl ketone, 6 parts of 40 percent aqueous NaOH, and 300 parts ofdimethyl sulfoxide. The mixture is stirred and heated to 50 C., where itis kept for 48 hours. The mixture is then cooled to room temperature andwater is added. The mass is then cooled further to about 10 C. Theproduct which is recovered therefrom in superior yield is4,4'-(1,2,2-trimethylpropylidene) -'bis-[2- 6-phenyl-n-hexyl)-6-benzylphenol].

Some other phenols which are used in place of the phenol described inExample 4 and the products which are obtained are listed below. Theamount of phenol used is the molar equivalent of the amount of2-(6-phenyl-nhexyl)-6-benzylphenol specified.

Phenol Bis-Phenol Product 2-see-butylphenol4,4-(1,2,2-trimethylpropylidene)- bis-(2-seobutylphenol).

4,6-(1,2,2-trimethylpropylidene)- bis-(Q-see-butylphenol)6,6-(1,2,2-trimethylpropylidene)- bis-(2-see-butylphenol)2benzyl-6-(a,a-di rnethy1benzyl) 4,4!(1,2,Z-trimethylpropylidene)-benzyl) phenol]. 2,6-d1phenethylphenol 4,4-(1,2,2-trimethylpropylidene)-bis-(2,6-diphenethylphenol) 2,4-diphenethylphenol 6,6(1,2,Z-trimethylpropylidone) EXAMPLE 7 A reaction vessel equipped as inExample 3 is charged with 192 parts of 2-methyl-6-n-hexylphenol, 162parts of methyl-n-pentyl ketone, 5 parts of 36 percent hydrochloric 11dabove. The amount of carbonyl compound used is the molar equivalent ofthe benzyl-n-hexyl ketone.

Carbonyl Compound Bis-Phenol Product 10 C. The product Which isrecovered therefrom in good Math l- 3- len ln- '0 l 4,4 1- eth l-4- l nlb t 1'- yreld 18 4,4 (l methylhexyhdene) bis (2 methyl 6 n g' p y p p gg i r i ga v t sg hexylphenol). benzyl) phenol].

Following is a 11st of phenols WhlCh, when used in place 2g s -p y y 54-g i p y l- -g s t g of the phenol described in Example 7, yieldbisphenol e iiim th iin z iiiiiefiiiir products listed on the right. Thequantity of phenol used n-Pentylphenethylketone g y g g 1 in each caseis the molar equivalent of the amount of 2- i ldii (arm y any) methyl6-n hexylphenol used in the example above, P11611371 tald yd p y -lnihexyllll-fidd-methylbenzyl) p eno Phenol IB' -Phenol P oduct 15 r 15EXAMPLE 10 2-methyl-G-n-dodecylphenol dfigtlljllgtljgthglxlggggnf)E2361)A reaction vessel equipped as in Example 3 is charged2-ethyl-6-n-decylphenol ,4(2-tlt-ilnel lyllexyllidle ilggusi f g f g' yI y y p 18110 p eno parts 0 met y -nexy etone, 4 parts 0z'methyl'whlomphenol i$$fififi2$ percent hydrochloric acid, and 440parts of dimethyl 2,6-di-n-l1eptylphenol 4,4(l-m thyle xylid isulfoxide. The mixture is stirred heated to 90 C. and

(2,6-di-n-heptylphenol). h 1 2 n pmpy1 6 n dodecylphenol 4AAumethylhexylidene) MS e d there for 34 hours. The mixture is then cooledto 241% t Mm ndec l hem} 6 fig ggg fig figggglpgggf room temperature,water is added, and the mixture is p y u yp 'cgmhepmhnfmdecylphenol)cooled further to about 10 C. An excellent yield of the ?rnheXy1-4-methvlphen01 y y 5 product 4 4'-(l-methylheptylidene)-bis-[2-isobutyl-6-(u oc- (2-n-l1exyl-4-methylphenol) 2-isop1'0pyl-4-(Z-n-butylphenyl)a.6,6-(l-methylhexylidene)-bisy ybp l, 1S recovered therefroml i fi py1 uy p l Listed below are other carbonyl compounds which are p used inplace of the methyl-n-hexyl ketone in the above example. The bisphenolproducts which are obtained are listed also. The amount of carbonylcompound used is A LE 8 the molar equivalent of the amount of the ketonede- A reaction vessel as equipped in Example 3 is charged scribed m'Examp 1e with 356 parts of 2-ethyl-6-isobutylphenol 182 parts of c b 10d benzophenone, 450 parts of dimethyl sulfoxide and 5 parts 35 in (myOmpmm BIS Phenol Product of 50 percent sulfuric acid. The mixture isheated to 100 H 'l--d lkt 4,4'-- C. and stirred for 28 hours. Themixture is then cooled n 6W n my 6 one u-linlfiiit fe iiifl iiii itiitoroom temperature. Water is added. The mass is then B t 1 4beilzynphenoli- ,4'- t 1 stirred and cooled further to about 15 C. Theproduct, u i afiafii$difiiiilfi 4,4(diphenylmethylene)-bis-(2-ethyl-6-isobutylphenol) 4O Levuhm fifigfgjifggi is isolated therefrom in excellent yield. dimethylbeuzyl) rieneiiiListed below are other carbonyl compounds and the Fmmaldehyde bisphenolproducts obtained when these carbonyl com- Diisobutylketone4,4-fil-isoput i s-meth lout u-' pounds are used in place of thebenzophenone in Exg ifg gffigi qa gfggfi' ample 8. In each case, theamount of carbonyl compound Ethyl (2-ethyl-n-hexyl) keto11e.4,4-1,3-diethylheptylidene)-bisused is the molar equivalent of theamount of benzoga f fi fgf phenone shown. y p n EXAMPLE l1 CarbonylCompound Bis-Phenol Product A reaction vessel as equipped in Example 3is charged I With 262 parts of 2-n-octyl-6-isobutylphenol, 171 partslrButYPmethYlketone t ggfilggggggfi figfg i of dusopropyl ketone, 110parts of diphenyl sulfoxide, n-Hexyl-(-biphenylyl) ketone 4, i;- 1-2+i?i i1ie1 1 g pairm s 400 parts of rsopropanol, and 5 parts of 45percent pofl Naphthyl n nonylketone a 4 gi3 fi :32 tassium hydroxide.The mixture is stirred and heated to bis-(Z-ethyl-fi-isobutylphenol). 70C. It 18 held there for 32 hours. The mixture is then Heptanal ig fg e ffi jgg cooled to room temperature, water is added and the massBenzaldehyde 4,4benz ylidene-bis-(2ethyl-G- is cooled further to about15 C. A good yield of the lsobutylphenonproduct, 4,4'-l-isopropy1-2-methy1propylidene)-bis-(2-noctyl-fi-isobutylphenol), isrecovered therefrom.

Example 11 is carried out as efiectivel wh th y en 0 er EXAMPLE 9sulfoxides are used in place of the diphenyl sulfoxide in To thereaction vessel as equipped in Example 3 are the same quantity as in theexample. Illustrative examples added 450 parts of2-n-heXyl-6-(u-methylbenzyl) phenol, of other sulfwgides are p p yh/sulfoxide. 204 parts of benzyl-n-hexyl ketone, 5 parts of 45 percent p yp y SulfOXide, methyl Phenyl SulfOX" aqueous potassium hydroxide, 180parts of dimethyl lde, Y Y SulfOXide, y SulfOXidesulfoxide, and 220parts of dimethyl carbitol. The mixture is stirred, heated to 160' C.and kept there for 1 EXAMPLE 12 hour. Then, this mixture is cooled toroom temperature To a reaction vessel equipped as in Example 3 are andwater is added. The mass is stirred and cooled furadded 536 parts of2-n-pentyl-6-(a-methylbenzyDphenol, ther to about 10 C. The productwhich s recovered in 208 parts of n-nonyl phenyl ketone, 5 parts of 36percent good y1eld 1s 4,4 -(1-benzylheptyl1dene)-b1s-[2-n-hexyl-6-hydrochloric acid, 300 parts of diethyl sulfoXide, and 700(a-methylbenzyl) phenol]. parts of isopropanol. The mixture is heatedwith stirring Listed below are carbonyl compounds and the blsphenol to130 C. and held there for 28 hours. This mixture is products obtainedwhen these carbonyl compounds are cooled to room temperature. Water isadded with stirring. used 1n place of the benzyl-n-hexyl ketone 1n theexample The mixture is then further cooled to about 15 C. The

EXAMPLE 13 To a reaction vessel equipped as in Example 3 are added 176parts of o-cyclohexylphenol, 147 parts of cyclohexanone, 5 parts of 45percent potassium hydroxide and 280 parts of dimethyl sulfoxide. Themixture. is

heated with stirring to 145 C. and held there for 22 hours. This mixtureis then cooled to room temperature and water is added. The mixture isstirred and further cooled to about C. The product,4,4-cyclohexylidenebis-(2-cyclohexylphenol), is isolated therefrom.

The types of sulfoxides described in Examples 11 and 12 may be used inplace of any sulfoxide in any of the Examples 1 through 13 above withoutaffecting ef'riciency of the invented process.

Reaction media such as isopropanol or dimethyl carbitol may also be usedin the systems described in Examples 1 through 13, if desired; thepresence or absence of such diluents does not limit the effectiveness ofthe invented process.

It is not always necessary to isolate the alkylidene bisphenols obtainedin this process. For example, when the bisphenol is to be used as anintermediate in preparing another compound, the reaction mixturecontaining the bisphenol product can be used directly. When isola tionof the alkylidene bisphenol from a reaction mixture is required, then itis to be understood that any of the accepted methods effecting therecovery may be used, as for example, by distillation, crystallizationor chromatographic separation.

The products of this process, the alkylidene bisphenols are Widely usedas antioxidants and stabilizers in lubricants, elastomers such asnatural rubber, polybutadiene, ethylene propylene terpolymer;thermoplastic resins such as polyethylene, polypropylene and polyvinylchloride; and in plasticizers such as dioctyl phthalate, diisodecylphthalate and dicresyl phthalate. In addition, these alkylidenebisphenols are useful as intermediates in the manufacture of resins suchas epoxy resins and polyester resins.

I claim:

1. A process for the production of alkylidene bisphenols, said processcomprising reacting (a) a phenol having the formula (Int with (b) acarbonyl compound having the formula Ra-C 4 wherein R R R and R areindependently selected from the group consisting of hydrogen, alkylradicals containing 1-12 carbon atoms, aryl radicals containing 6-12carbon atoms, aralkyl radicals containing 7-12 carbon atoms and alkarylradicals containing 7-12 carbon atoms, in the presence of a sulfoxidehaving the formula wherein R and R are independently selected from thegroup consisting of alkyl radicals containing 1-8 carbon atoms and arylradicals containing 6-12 carbon atoms, within a temperature range of to250 C.

2. The process of claim 1 wherein R and R are alkyl radicals containing1-8 carbon atoms.

3. The process of claim 1 wherein R and R are methyl radicals.

4. The process of cl airn 1 wherein R and R are alkyl radicalscontaining 1-12 carbon atoms.

'5. The process of claim 4 wherein R and R are selected from the groupconsisting of hydrogen, alkyl radicals containing 1-12 carbon atoms andaralkyl radicals containing 7-12 carbon atoms.

6. The process of claim 4- wherein R and R are selected from the groupconsisting of hydrogen and alkyl radicals containing 1-12 carbon atoms.

7. A process for the production of alkylidene bisphenols, said processcomprising reacting a phenol having the formula wherein R is ana-branched alkyl radical containing 3-12 carbon atoms and R is an alkylradical containing 1-12 carbon atoms, with a carbonyl compound havingthe formula 0 L R3' (J R4 wherein R and R are alkyl radicals containing1-12 carbon atoms, in the presence of a sulfoxide having the formula:

UNITED STATES PATENTS 2,359,242 9/1944 Perkins et al. 260-619 BERNARDHELFIN, Acting Primary Examiner.

5 H. ROBERTS, Assistant Examiner,

1. A PROCESS FOR THE PRODUCTION OF ALKYLIDENE BISPHENOLS, SAID PROCESSCOMPRISING REACTING (A) A PHENOL HAVING THE FORMULA